The disclosure relates generally to layout of a circuit member and, more particularly, to a circuit member layout with enhanced performance.
Modular jack (“modjack”) receptacle connectors mounted to printed circuit boards (“PCBs”) are well known in the telecommunications industry. These connectors are often used for electrical connection between two electrical communication devices. With the ever-increasing operating frequencies and data rates of data and communication systems and the increased levels of encoding used to transmit information, the electrical characteristics of such connectors are of increasing importance. In particular, it is desirable that these modjack connectors do not negatively affect the signals transmitted and where possible, noise is removed from the system.
When used as Ethernet connectors, modjacks generally receive an input signal from one electrical device and then communicate a corresponding output signal to a second device coupled thereto. Magnetic circuitry can be used to provide conditioning and isolation of the signals as they pass from the first device to the second and typically such circuitry uses components such as a transformer and a choke. The transformer often is toroidal in shape and includes a primary and secondary wire coupled together and wrapped around a toroid so as to provide magnetic coupling between the primary and secondary wires while ensuring electrical isolation. Chokes are also commonly used to filter out unwanted noise, such as common-mode noise, and can be a toroidal ferrite used in differential signaling applications. Modjacks having such magnetic circuitry are typically referred to in the trade as magnetic jacks.
In some instances, the wires from one transformer and choke subassembly may impact the performance of adjacent subassemblies. As system data rates have increased, systems have become increasingly sensitive to cross-talk between ports and even between channels within a port. Magnetic subassemblies that operate within a predetermined range of electrical tolerances at one data rate (such as 1 Gbps) may be out of tolerance or inoperable at higher date rates (such as 10 Gbps). Accordingly, improving the isolation between the channels of the magnetic jacks has become desirable in order to permit a corresponding increase in the data rate of signals that pass through the system. Cross-talk and electro-magnetic radiation and interference between channels may impact the performance of the magnetic jack (and thus the entire system) as system speeds and data rates increase. Improvements in shielding and isolation between channels as well as simplifying the manufacturing process of a magnetic jack is thus desirable.